A sick young man wrapped in a tartan blanket lies on a sofa beside a blonde young woman holding a mug, in a cosy lamplit apartment.

Original artwork, not a still

Sheldon Cooper

Soft kitty, warm kitty, little ball of fur.

— The Big Bang Theory

Behind the line

What it means

Our interpretation.

A grown physicist turns into a toddler the moment he has the sniffles, and a nursery rhyme is the only cure. It gave the series its tenderest running gag and a glimpse of the mother behind Sheldon's rigidity. Outside the show the song is a real children's tune, which surprised many fans, and it turned up on mugs and plush toys for years.

Context reviewed

In context

Spoilers for The Big Bang TheoryShow the scene

The song first appears in "The Pancake Batter Anomaly" (season 1, episode 11, March 31, 2008). Sheldon catches a cold, Leonard, Howard and Raj flee his whining, and Penny is left to look after him. Sheldon wants the song his mother sang to him when he was ill, and Penny sings it to him. It returns whenever he is sick or homesick, including a later episode where Penny sings it again after he is locked out of his apartment and has to sleep over at hers.

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Context reviewed

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